Data Link Connector: Testing and Inspection

1992 Volvo 740 L4-2320cc 2.3L DOHC B234F (Can)SECTION Testing and Inspection


NB. Checking data link connector (DLC)

NB1




Checking LED
- Ignition on.
- Press the DLC button.
The LED should light when the button is down.

If the LED does not light
^ check battery power NB2.

If the LED lights
^ check the power supply from the control module NB4.

NB2




Checking the battery power
- Ignition on.
Connect a voltmeter between terminal 4 in the connector and GND.
The voltmeter should read battery voltage.

If this value is OK
^ check the GND point NB3.

If the reading is incorrect
^ check the fuse and the wiring to it for breaks in accordance with NA2. NA. Checking the Wiring

NB3




Checking the GND point
- Ignition off.
Connect an ohmmeter between terminal 8 in the connector and GND.
The ohmmeter should read approx. 0 ohms.

If this value is OK
^ try using a new DLC.

If the reading is incorrect
^ check the GND point and the wiring to it for breaks in accordance with NA2. NA. Checking the Wiring

NB4




Checking the power supply from the control module
- Ignition on.
Connect a voltmeter between terminal 2 in the connector and GND.
Connect a voltmeter between terminal 6 in the connector and GND.
The voltmeter should read more than 5 volt in both cases

If the readings are OK
^ replace the DLC

If the reading is incorrect
^ check the wiring between the control module and the DLC for breaks or grounding in accordance with NA2 and NA3. NA. Checking the Wiring
RENDER: 1.0x

NO RELATED

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